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Question:
What is the S-cam used for?
A
To apply the brakes.
explanation
S-cam Brakes. When you push the brake pedal, air is let into each brake chamber. Air pressure pushes the rod out, moving the slack adjuster, thus twisting the brake camshaft. This turns the s-cam (so called because it is shaped like the letter "S"). The s-cam forces the brake shoes away from one another and presses them against the inside of the brake drum. When you release the brake pedal, the s-cam rotates back and a spring pulls the brake shoes away from the drum, letting the wheels roll freely again. [Commercial Driver's License Manual]
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EdgarCeja26
6 years ago
Great app
Myles Blake High School
6 years ago
I only got 2 questions wrong
Tim de Bear
6 years ago
In the midst of finishing up learning on the older app, it told me to download this newer version. However, I didn’t want to have to go through all those questions again, so I simply finished reviewing on the old app and took the practice test on this newer app. Upon completion of the tests, it would not let me move forward or see my score! How should I know if I have done well enough to pass if I cannot see my own score?